Outboard motor anti-tilt locking mechanism

ABSTRACT

A tilt lock mechanism for an outboard motor incorporating locking fingers actuated by a flexible shaft driven by a channel cam keyed to the shift shaft of the engine. A readily disassemblable ball joint links the flexible operating shaft to a rotating mechanism carrying the locking fingers.

United States Patent [191 Kloiber 1451 Jan. 15, 1974 OUTBOARD MOTOR ANTI-T1111 LOCKKNG MECHANISM [75] Inventor: Robert 1F. Kloiber, Oshkosh, Wis.

[73] Assignee: Brunswick Corporation, Skokie, I11.

22 Filed: Aug. 14, 1972 21 Appl. No.: 280,272

52 us. or. 115/17, 115/41 R 51 1111.01 B6311 1/14 [58] Field of Search 115/11, 12 R, 12 A,

115/17, 18 R, 18 B, 29-34, 37-38, 42; 123/195 R, 195 P, 195 C, 198; 64/30 A; 74/567 [56] References Cited UNITED STATES PATENTS 2,916,007 12/1959 Kiekhaefer 115/18 R 3,051,119 8/1962 Hamlyn et a1 115/41 R 2,635,576 4/1953 Kiekhaefer 115/18 R 2,702,517 2/1955 Armstrong 115/18 R 2,718,792 9/1955 Kiekhaefer 115/34 R Primary Examiner-Duane A. Reger Assistant Examiner-Jesus D. Sotelo Attorney-Wi1liam G. Lawler, Jr.

[5 7 ABSTRACT A tilt lock mechanism for an outboard motor incorporating locking fingers actuated by a flexible shaft driven by a channel cam keyed to the shift shaft of the engine. A readily disassemblable ball joint links the flexible operating shaft to a rotating mechanism carrying the locking fingers.

9 Claims, 6 Drawing Figures PATENTEDJM 1512114 3,785.;328

OUTBOARD MOTOR ANTI-TILT LOCKING MECHANISM BACKGROUND OF THE INVENTION Outboard motors are typically mounted on the transom of a boat in a manner which permits the power head to be tilted forward raising the drive shaft hosuing and propeller out of the water. In addition to facilitating trailering of the boat with the motor attached, freedom for such tilting is desirable when the motor is engaged in the forward gear so that the motor may swing upwardly and over obstructions passing under the boat. However, when the engine is reversed, it is well recognized that such tilting up must be prevented if the motor is to be effective in pulling the boat stern first. Accordingly, tilt lock mechanisms of various sorts are known to the art.

The more sophisticated reverse tilt lock mechanisms may be engaged automatically when the engine is shifted into reverse. One such mechanism is illustrated in U. S. Pat. No. 2,635,576, E. C. Kiekhaefer, Shift- Speed Control for Outboard Motors, where rotation of a cam 58 raises an arm 66 rotating finger hooks 63 into engagement with his horizontal positioning pin 61.

One problem experienced with the Kiekhaefer design was the lack of flexibility to permit the finger hook to slide over the locking pin and into the engaged position in the event that the engine was shifted to to reverse while tilted forward so that the locking hook could not initially engage the locking pin.

It is an objective of the invention to provide an antitilt locking mechanism with a flexible linkage that will permit the locking hook to flex upwardly and subsequently engage the tilt pin on the engine mount should the engine swing down with the locking hook in the engaged positon.

Further, it is an objective of the flexible linkage of the invention to permit the locking hook to flex upwardly out of engagement with the tilt pin should the amount of reverse power applied by the engine exceed a predetermined safe level.

Another objective of the invention is to provide for positive movement of the actuating arm for the locking hook through the use of a double acting cam, as opposed to reliance upon the combination of a single cam surface and rider retained thereon by spring action.

A still further objective of the invention is the incorporation of a snap-on retainer for the tilt lock actuating rod which greatly facilitates assembly, disassembly and part replacement.

DETAILED DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial side view of an outboard engine illustrating the tilt lock mechanism of the invention in the locked position.

FIG. la is a perspective view of the cam support element of FIG. 1.

FIG. 2 is a partial side view of an outboard motor illustrating the tilt lock mechanism of the invention in the disengaged position.

FIG. 3 is an enlarged perspective view showing the tilt lock mechanism of the invention in the disengaged position.

FIG. 3a is a cross-sectional view of a portion of the linkage of the invention taken along line 3a-3a of FIG. 3.

FIG. 4 is an enlarged perspective view illustrating the cam actuating mechanism of the invention when the tilt lock is in the engaged position.

DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. I, the clamp bracket ll of an outboard engine 2 is illustrated as engaged upon the transom 3 of a boat with the engine in the fulldown position and the antitilt mechanism engaged. For purposes of simplicity, unrelated detail of the engine itself has been omitted.

The tilt lock mechanism is actuated by the rotation of a shift shaft 5 as will be explained. The shift shaft 5 and its actuating mechanism are well known to the art and need not be described herein.

The tilt lock mechanism of the invention is comprised basically of a pair of locking fingers 6 attached to a sleeve 7 which rotates in the vertical plane in com- I pany with a horizontal pin approximately journaled at its ends to the motor housing. Rotation of the hooks 6 is accomplished through up and down motion of an actuating rod 10, the upper end of which is connected by a ball joint 111 to a lever arm 12 rigidly attached to the sleeve 7. Upward movement of the rod 10 rotates the sleeve '7, moving the hooks 6 into the engaged position upon the tilt pin 14 as illustrated in FIG. I. Downward movement of the actuating rod 10 elevates the hook 6 to the disengaged position as illustrated in FIG. 2.

The actuating rod is moved upwardly and downwardly by a cam 15 keyed to the shift shaft 5. The lower end 16 of the rod It) is adapted to ride within a cam channel 17 molded into the body of the cam 15. A cam supporting bracket and rod guide 118 affixed to the drive shaft housing 19 supports the cam 15 vertically upon the shift shaft 5 and keeps the lower end to of the actuating rod 110 engaged within the channel 17 and the cam 15.

The cam channel 17 is shaped and oriented as illustrated so that counterclockwise rotation of the shift shaft 5 (when viewed from above) raises the actuating rod 10 engaging the tilt lock, while clockwise rotation of the shaft lowers the rod lltl disengaging the tilt lock. One of the most significant features of the invention is that the cam following portion 16 of the actuating rod It) is positively displaced by the sides 55 and 56 of the cam channel 117 upon clockwise or counterclockwise rotation of the cam 15 so that the locking and unlocking action of the tilt lock is under positive control at all times.

The cam 15 is retained in vertical position upon the shaft 5 by the bracket 18. Upward motion of the cam 15 is limited by a flange 57 which extends radially around the cam body 50 and bears against the lower surface 58 of the bracket 18. Referring to FIG. la, downward motion of the cam is limited by the action of a pair of ears 20 which extend radially from the upper extremity of the cam body 50 and engage the upper surface 59 of the bracket 18. The cam 15 may be disengaged from the bracket 18, after the actuating rod 10 has been removed, by rotating the cam body 50 until the ears 20 line up with a matching pair of slots 21 radiating from the bore 22 through the bracket 18.

With the mechanism assembled, the interaction of the end 116 of the actuating rod 10 with the terminal ends of the cam channel 117 prevents rotation of the cam body 15 to the point where the wings 2th will align with the slots 21, and thus prevent the cam 15 from falling below the bracket 18.

The actuating rod 10 has a bend 25 proximate the midsection thereof to promote flexing when the rod is subjected to compression forces resulting from forced engagement or disengagement when the hooks 6 are in the locked position. While the degree of flexibility desired will determine the diameter and length of the rod 10; a inch diameter rod of nylon 66 has been found acceptable for use with outboard engines up to 20 horsepower.

Referring to FIGS. 3 and 3a, the upper end of the actuating rod 10 constitutes a ball 26 which is retained within the lever arm 12. The lever arm 12 is comprised of two spaced apart and parallel sides 27 and 28. Within each side is a cylindrical depression 29 having a radius comparable to the ball 26. The depressions 29 terminate short of the bottom 30 of the arm 12, and form the side portions of a cylindrical bore having a radius comparable to that of the ball 26. The sides 27 and 28 are spaced apart sufficiently to permit the body 32 of the actuating rod 10 to pass therebetween, but close enough together so that the cylindrical depressions 29 engage and guide the ball 26 as it it slid downwardly therebetween from above.

The ball 26 is retained within the cylindrical bore by a snap-on cover 34, the left end of which has an inverted T-shaped portion 35, the cross-portion of which engages beneath a pair of extensions 36 protruding from the left ends of the sides 27 and 28 respectively. The opposite end of the cover 34 is then engaged downwardly and around the pin 7 by flexing it outwardly as indicated by the arrow 37 and pressing it down over the pin 7. Guide walls 38 extend along the top outer edges of sides 27 and 28 and above the sides of the snap-on cover 34 holding it in place along the top thereof. As a result of this structure, the actuating arm 10 can be disengaged from the lever arm 12 by simply removing the cover 34, lifting the rod 10 until the ball 26 clears its cylindrical retaining walls 29, and moving it out from between the sides 27 and 28. The bottom inside edges of the sides 27 and 28 are arcuately beveled beneath the cylindrical depressions 29, as at 40, to avoid abrasion of the actuating rod 10.

Referring to FIGS. 1, 3 and 4, the cam support and guide 18 has a bore 41 angularly disposed therethrough large enough to permit the lower end 16 of the actuating rod to be inserted therein and maneuvered into the cam channel 17. With the cam 15 and rod end 16 engaged as shown, rotation of the rod 10 which would defeat the camming action is prevented by a U-shaped housing 42 which extends downwardly from the bore 41 and opens only in the direction of the common axis of the cam 15 and shift shaft so that the sideward component of the forces exerted on the end 16 of the rod are resisted by the side portions of the guide housing 42. The closed back 43 of the guide housing 42 is angled so as to be generally parallel to the lower portion of the rod 10 where it passes therethrough, thereby providing a substantial area of contact resisting withdrawal of the end 16 of the rod 10 from the channel 17 of the cam 15. With the rod 10 disengaged from the lever arm 12, which may be accomplished by removing the cover 34 and rotating the hooks 6 counterclockwise, the rod 10 may be disengaged from the cam by generally moving its upper extremity in the direction of the shift shaft 5 and maneuvering until clear of the retaining member 18.

Referring to FIGS. 3 and 4, the cam is comprised of a cylindrical body having a bore 51 therethrough to receive the shaft 5. A series of lands 52 within the bore 51 mesh with matching channels 53 on the shift shaft 5 so that the cam 15 rotates with the shaft 5. A built up portion 53 molded integrally with the cam body 50 contains the cam channel 17. The cam channel 17 and the lower end 16 of the actuating rod 10 are compatibly sized so that the rod end 16 will ride within the channel 17 without binding. To assure smooth action and to avoid any possibility of corrosion, the cam may be made of 33% glass-filled nylon, and the actuating rod may be made of nylon 66.

In the configuration of the invention illustrated two cam surfaces are operative. The upper surface 55 of the cam channel 17 bears upon the top of the rod end 16 when the shift shaft is rotated clockwise driving the actuating rod 10 downwardly and raising the hook 6. The lower side 56 of the cam channel 17 operates upon the lower side of the rod end 16 when the shift shaft is rotated counterclockwise, driving the rod 10 upwardly and rotating the locking hook clockwise into the engaged position.

While the principles of the invention have been described in connection with the above specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of the invention.

I claim:

1. In an outboard motor having a mounting bracket and means for tilting the motor with respect to said bracket, an improved means for selectively preventing such tilting comprising:

a latch mechanism having an engaging element and an engaged element, and means for moving said engaging element into and out of engagement with said engaged element, comprising;

a driving cam and means for operatively linking said engaging element to said driving cam;

said driving cam having a first cam surface operative through said linkage to positively urge said engaging element to engage, and a second cam surface operative through said linkage to positively urge said engaging element to disengage.

2. The device of claim 1 wherein said linking means includes an actuating rod, one end of which comprises a follower for said first and second cam surface and means for removably coupling the other end of said rod to said engaging element, including resilient means for retaining said rod and engaging element in the coupled condition.

3. The device of claim 2 wherein said rod is made of a resilient material, and wherein said rod is nonlinear, so that it is flexible and predisposed to bend when subjected to compressive force in excess of a preselected value.

4. The device of claim 3 wherein said engaging element includes a lever arm and means for pivotally connecting the other end of said rod to said lever arm including non-metallic resilient means for maintaining the connection of said rod to said lever arm.

5. ln an outboard motor including a power head, a drive train including forward and reverse gears, a drive shaft housing, and a shift shaft for shifting said gears, an improved anti-tilt locking mechanism comprising:

latch means into and out of the engaged position is positively controlled. 6. The device of claim 5 wherein said rod is made of a resilient material, and the axis of said actuating rod defines an obtuse angle so that said rod has a predisposition to flex when subjected to a compressing force applied to the ends thereof.

7. The device of claim 6 wherein said means for connecting said operating rod to said latch means comprises:

a ball and socket joint wherein the ball is attached to the actuating rod and said socket comprises a cylindrical channel in said latch means adapted to receive said ball therein, and a resilient removable cover means for closing the channel and retaining said ball therein.

8. The device of claim 5 further comprising means for axially supporting said driving cam on said shift shaft and means for retaining the follower end of said rod in lateral position with respect to said cam surfaces.

9. The device of claim 5 wherein an end portion of said one end of said rod extends laterally thereof, said cam surfaces are generally laterally disposed with respect to said actuating rod, and engage the upper and lower sides of the cam follower end of said actuating 

1. In an outboard motor having a mounting bracket and means for tilting the motor with respect to said bracket, an improved means for selectively preventing such tilting comprising: a latch mechanism having an engaging element and an engaged element, and means for moving said engaging element into and out of engagement with said engaged element, comprising; a driving cam and means for operatively linking said engaging element to said driving cam; said driving cam having a first cam surface operative through said linkage to positively urge said engaging element to engage, and a second cam surface operative through said linkage to positively urge said engaging element to disengage.
 2. The device of claim 1 wherein said linking means includes an actuating rod, one end of which comprises a follower for said first and second cam surface and means for removably coupling the other end of said rod to said engaging element, including resilient means for retaining said rod and engaging element in the coupled condition.
 3. The device of claim 2 wherein said rod is made of a resilient material, and wherein said rod is nonlinear, so that it is flexible and predisposed to bend when subjected to compressive force in excess of a preselected value.
 4. The device of claim 3 wherein said engaging element includes a lever arm and means for pivotally connecting the other end of said rod to said lever arm including non-metallic resilient means for maintaining the connection of said rod to said lever arm.
 5. In an outboard motor including a power head, a drive train including forward and reverse gears, a drive shaft housing, and a shift shaft for shifting said gears, an improved anti-tilt locking mechanism comprising: a cam mounted upon and rotating with the shift shaft; an actuating rod, one end of which comprises a follower for said cam; latch means responsive to movement of said actuating rod for locking the drive shaft housing in the down position; and means for operatively connecting the other end of said actuating rod to said latch means; said cam comprising a first surface operative to raise said actuating rod and a second surface operative to lower said actuating rod; whereby movement of said actuating rod and said latch means into and out of the engaged position is positively controlled.
 6. The device of claim 5 wherein said rod is made of a resilient material, and the axis of said actuating rod defines an obtuse angle so that said rod has a predisposition to flex when subjected to a compressing force applied to the ends thereof.
 7. The device of claim 6 wherein said means for connecting said operating rod to said latch means comprises: a ball and socket joint wherein the ball is attached to the actuating rod and said socket comprises a cylindrical channel in said latch means adapted to receive said ball therein, and a resilient removable cover means for closing the channel and retaining said ball therein.
 8. The device of claim 5 further comprising means for axially supporting said driving cam on said shift shaft and means for retaining the follower end of said rod in lateral position with respect to said cam surfaces.
 9. The device of claim 5 wherein an end portion of said one end of said rod extends laterally thereof, said cam surfaces are generally laterally disposed with respect to said actuating rod, and engage the upper and lower sides of the cam follower end of said actuating rod. 